Yes, strange. Because (from checking the latest spec file)
in igraph spec you write
----------------------------------------------------
+Provides: %{name}-%{version}
----------------------------------------------------
Obviously, this is expanded as "Provides: igraph-0.5". Why do you
want this Provides? Also, from your newest igraph spec file igraph-devel
provides: "Provides: igraph-devel-0.5".
Note that a rpm with a EVR always provides "Provides: <the name of rpm> =
%{?epoch:%epoch:}%{version}" as well as "Provides: <the name of rpm> =